Stonybrook, Pennsylvania Weather
Queen Anne's lace lines the roads. Day 16 of summer. Read this microseason across nine climate regions →
Stonybrook weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 6Light Rain83%0.12″77°69°—
- TuesdayJul 7Light Drizzle13%—81°66°+4°
- WednesdayJul 8Light Drizzle20%—77°63°-4°
- ThursdayJul 9Thunderstorm71%0.01″84°67°+7°
- FridayJul 10Thunderstorm43%—81°68°-3°
- SaturdayJul 11Drizzle24%0.15″74°69°-7°
- SundayJul 12Light Drizzle22%0.04″74°65°0°
AQI 48 (Good), driven by Ozone. Ozone at AQI 76 — peak already passed at 1 PM under overcast skies. Levels should ease through evening.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 76 — peak already passed at 1 PM under overcast skies. Levels should ease through evening.
- Present
- AQI 76
- UV peak
- 1.7 at earlier today
- Sky at peak
- overcast
- Projected peak
- AQI 76
PM × Wind × Precip
PM2.5 at 11.6 µg/m³, PM10 at 12.4 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.94
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- background
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).








































When the stars begin to huddle, the earth will soon become a puddle.
- Moonrise
- 11:47 PM
- Moonset
- 12:23 PM
- In sign
- ♈︎ Aries
Queen Anne's lace lines the roads
Stonybrook at a glance
- Today vs. normal: 5°F above the seasonal normal for this latitude
- Last frost: April 16 (climatological average for this latitude)
- Microseason: Jul 6–10
- Planting window: Sow fall broccoli and cabbage indoors for transplant in 4 weeks.
16-Day Forecast — Stonybrook
- Mon77°69°83%
- Tue81°66°13%
- Wed77°63°20%
- Thu84°67°71%
- Fri81°68°43%
- Sat74°69°24%
- Sun74°65°22%
- Mon84°62°14%
- Tue86°63°12%
- Wed87°69°14%
- Thu79°63°20%
- Fri74°57°29%
- Sat79°59°36%
- Sun82°59°35%
- Mon83°62°33%
- Tue83°64°27%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of July 6, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
SPC Convective Outlook
Storm Prediction Center — Stonybrook
SPC includes Stonybrook in the general thunderstorm area today — no severe risk, but storms are possible.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3NONENo severe risk
Thunderstorms possible. Not severe, but capable of producing lightning and brief heavy rain.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.
Microseason · July 6–10
Queen Anne's lace lines the roads
Wild carrot blooms along roadsides and park edges.
Day 187 of 365 · Wedge 38 of 72
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
The year in Stonybrook tops out in July (~77°F) and dips lowest in January (~30°F), with December wettest at 3.8 inches and February driest at 2.7 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 30° | 3.1″ | 14 |
| February | 32° | 2.7″ | 13 |
| March | 41° | 3.4″ | 16 |
| April | 53° | 3.7″ | 17 |
| May | 62° | 3.8″ | 18 |
| June | 71° | 3.6″ | 16 |
| July | 77° | 2.9″ | 15 |
| August | 75° | 3.5″ | 17 |
| September | 69° | 3.3″ | 15 |
| October | 58° | 2.8″ | 13 |
| November | 44° | 3.6″ | 14 |
| December | 34° | 3.8″ | 14 |
Regional context
Stonybrook swings from 30°F in January to 77°F in July (47°F) per NOAA NCEI 1991-2020 normals; precipitation in Stonybrook runs about 40.2 inches on roughly 182 measurable days.
Stonybrook's precipitation spreads evenly: December peaks at 3.8 inches on 14.2 wet days, while February holds 2.7 inches over 13.0 — no month dominates Stonybrook's rain calendar. That lines Stonybrook up with places like Yorklyn, PA, Hallam, PA and Yorkana, PA, fed by overlapping storm tracks.
Stonybrook reaches its last hard frost near mid-April; that is the cue for kale, peas, spinach, and parsnips. Stonybrook's heat-lovers — tomatoes, peppers, squash — hold off until Stonybrook's frost risk clears, 10-14 days on. The season ends by mid-November in Stonybrook, once hard frosts set back in. A creek-bottom lot in Stonybrook can lag Stonybrook's last frost 7-10 days behind a south slope.
Similar climates: Yorklyn, PA, Hallam, PA, Yorkana, PA, East York, PA, Queens Gate, PA.
Frequently asked
- When does it freeze in Stonybrook?
- Stonybrook's last spring frost lands near mid-April, and in Stonybrook the first fall frost follows around mid-November.
- What is the rainy season in Stonybrook?
- Rainfall in Stonybrook peaks in December near 3.8 inches, out of about 40 inches annually.
- What is the warmest month in Stonybrook?
- On average July tops the year in Stonybrook at about 77°F.
- What is the coldest month in Stonybrook?
- The coldest stretch in Stonybrook falls in January, around 30°F on average.
- When can I start a vegetable garden in Stonybrook?
- In Stonybrook, sow peas and hardy greens around mid-April; Stonybrook's tomatoes and peppers wait two weeks more.
- How many rainy days does Stonybrook get?
- Stonybrook averages about 182 days with measurable rain or snow each year.
- What hardiness zone is Stonybrook?
- Since January in Stonybrook averages 30°F, Stonybrook's USDA zone follows that floor — confirm it by ZIP.
- What is the 10-day forecast for Stonybrook?
- Stonybrook's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in Stonybrook?
- See this week's day-by-day rain chances for Stonybrook in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Stonybrook?
- Current conditions for Stonybrook and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Stonybrook forecast updated?
- The Stonybrook forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Stonybrook?
- Today's sunrise and sunset times for Stonybrook are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
- How accurate is the weather forecast for Stonybrook?
- The next few days in Stonybrook's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Climate
Set in a warm-summer humid continental zone, Stonybrook, Pennsylvania swings from 30°F in the heart of winter to 77°F at midsummer — a 47°F arc.
Stonybrook sees close to 40 inches of precipitation annually, falling across some 182 wet days.
Stonybrook sits at 40.0°N; that 47°F seasonal swing frames planting windows and frost dates across Stonybrook.
ZIP codes in Stonybrook
- 17402